The blazer does not start..it makes a clicking sound. When it is jumped it starts. Then when turned off and turnd on again it doesn't start unless jumped again. I let it run for 30 minutes and the

Dead battery

Dangerous practice to try & jump a dead battery

The battery cables could be loose at either end or corroded internally

Most likely the battery is worn out, if original to car
since it was new, or the starter solenoid is worn

You do not want to jump any vehicle made after the
year 2000 or your asking for possible problems with
todays electronics.

You need a good battery that has been tested & fully
charged, then only jump with a jump pack,not another car

Most likely you have a bad connection somewhere. Trace the battery cables and clean/tighten all terminals or try jumping to a different lug. You might also try removing the starter and jumping directly to the starter to verify that it is good.

Make sure it's getting fuel. Try using some ether or starting fluid. If it rumbles to life but doesn't stay running then there's a problem with the fuel delivery system. i.e.... Fuel pump, clogged filter, pressure regulator.... If the ether doesn't change the results you are getting now then it's a fire or sensor problem. Ignition coil, relays, sensors not signaling, PCM... I wish you luck. Let us know how it turns out

it might be that you need a new battery as the is not inof power in that 1 to ture it over < try jump starting > that might put some life back in it if it start leave it running for 20 - 30 min or drive round min of 12 miles as that will charge it up more
i cant help much form hear i need to know more on what its doing and the sounds (eg) duss it make a clicking sound when key it turnd or just go dead no light nothing

I am the type that likes to jump start a car to troubleshoot it. If you jump start the car and it starts that tells you that the starter and engine is good and the problem is in your battery or alternator. If it doesn't start then I take the serpentine belt off and try to turn the engine with a large wrench. If it rotates, then I replace the starter and starter solenoid.

The clicking sound is coming from your starter solenoid. Which could mean your solenoid or starter or both are bad. But don't rush out and buy replacements until you have troubleshot the problem a little. First, try a jump start. If that works and the car starts, then either your battery is not putting out enough amperage to turn your engine over, which could mean your battery cables are corroded and not making good connection or your alternator is not charging your battery when the car is running. If it started, suggest you take it to an auto parts store and have them test your battery and alternator.

Now if it doesn't start when jump starting, you still need to do some more troubleshooting. Yes, it could be the solenoid and or the starter, but it could also be something internal to the engine. Take off the serpentine belt and try to turn the engine over with a large socket wrench. If it turns, then it is your starter/solenoid, if it doesn't then it is internal to your engine.

Is it one click or multiple clicks. If it's multiple clicks, it sounds like a dead battery. Voltage isn't always an indicator of a good battery, you need to have enough cranking amps to be able to start an engine also. If you have dash lights and it only clicks once, you could have a bad starter. An easy way to check this is to try and jump start the vehicle. If it starts up with a jump start, you need a new battery. If it still doesn't start up and it just clicks, you probably need a new starter.

Good Luck!
~Brandon

Hi, this is often caused by a low battery. Try a jump start. If that works, remove the jumper cables and check the voltage at the battery with the car still running. Voltage should be at least 14 volts DC. If not, remove the alternator and have it tested at your local parts chain. If the jump start doesn't work, please get back to me.

2006 cobalt won't start after a severe thunderstorm. Battery was check and is good, light turn on, turns signals work a/c blower works, however, radio does not.Doesn't even click or turn over. All seniors check out. What's the problem?

Well odds are that your blazer is fixed by now. Either way sounds like a bad battery, that's why you need jumps all the time. Why it would die, there are too many possibilties off hand. So what was wrong with it?